Gear transmission



July 1, 1.930. V Y.- KlkucH|' 1,768,850

GEAR TRANSMI S S ION Filed June 17, 1927 l atented July 1, 1930 i UNITEDSTATES YUKIO KIKUGHI, or Monrc Ain, nEwJERsnY GEAR TBAHMISSIQN 7Application filed June 17,

This invention relates to a gear transmission for use in transmittingthepower of a several speed gears, that is to say, first, second andthird, as well as reverse gears are constantly retained in mesh 1n theoperation of the transmission gearing, with meansniovably disposed onthe transmission gear shaft for placing separately, the various speedand drive gearings in operative connection therewith, said meansinvolving a series of clutches with means for actuating the same; afurther object being to provide means for automatically tightening theclutch member or members mounted on the transmission drive shaft in theengagement of the-movable clutches therewith; a, still furtherobjectbeing to provide, as a part of thetransmission mechanism, a clutchfor coupling and uncoupling the engine shaft to be driven, thuseliminating the-use of the usual clutch interposed between thetransmission'and engine; and with these and other objects in view, theinvention consists in an apparatus of theclass and for the purposespecified, which is simple in construction, efficient in use, and whichis constructed as hereinafter described and claimed.

The invention is fully disclosed in the following specification, ofwhich the accompanying drawing forms a part, in whichthe separate partsof my improvement are designated by suitable reference charactersin eachof the views, and in which Fig. 1 is a longitudinal, sectional viewthrough a transmission made according to my invention, part of theconstruction'being open in section and-in full lines; and, r

h Fig. 2 is a detail, plan view of a part 0 the construction shown inFig. 1.

In the drawing, 5 represents the transmission casing or housing inwhich-my improved transmission gearing -is mounted, said housing beingprovided at opposite ends with roller bearings 6 and 7 arranged in axial1927. "Serial No. 199,536.

alinementand for supporting the shafts or stub shafts Sand 9respectively. The shaft .8 represents; themember to be coupled with theengine or other power source, and the shaft 9, the member to be coupledwith the driven shaft or shafts, directly or indirectly.

.In the use ofthe apparatus in motor vehicles, it willibeunderstood thatthe shaft 9 is in operative connection with the differential mechanismin the rear axle housing, and thus coupledwiththe drive wheels of thevehicle. ml'lhe 'shaft 8, has Within the casing 5, an enlarged bodyhaving an external gear face 'SR-and; a clutch element 8 and an aperture8? forming, a bearing for one end of a transmissionshaft 10. In a likemanner, the shaft 9 has withinlthe casing 5, two external gearfaces9%and9 'and anaperture 9 forming a bearing for the. other end ofthe shaft 10.

1The, end portions of the shaft 10 are provided,with:clutch-members 11and 12, on which are ,slidablyi mounted, clutches 18 and 14respectively. The clutch 13 has an internal clutch element, 13 adaptedto mesh with the clutcli element 8 andthe clutch 14 has aisimilarinternal clutch element 14, adapted toinesh with the 'gean9 In thedirect, third orliigh speed drive, the clutches 13 and 14; are in meshwith: the clutch element 8 and gear 9' respectively,'providinga directcoupling of the shaft '10 with the shafts 8 and 9 as "will'be'understood. The clutch 1& is normally held inengagenient with-the. gear9" by asp-ring lat and is moved out'of engagement therewith by a lever.15 pivoted as seen at .16, andwhi'ch is actuatedthrough a foot pedal orother control .17 through a link 18, diagrammatically illustrated inFig. 1 of the drawing. The pedal 17 functions as a clutch pedal ofiamotor vehicle or'any other control 9 may be-used; Mounted in the casing5 below thez shaft 10 is a supplemental shaft '19 to which'is securedfour gears 20,121, 22 and 23. ThegearQOmeshes at alltimeswith the gear:Se, hile the gears 21, 22 and -23meshwith .clutchmembers or gearfaceson clutchmembers-.24c,}2 5 and26 respectively.

, I lhe members2 l, 25 and 26 are freely rotatable e'on bearings 27, 28'and 29 mounted on and slidable longitudinally of the shaft 33 ontheshaft 10 10 to a slight degree suflicient to bring the beveled clutchfaces 24, 25 and 26 thereof in engagement with the peripherial faces ofconical clutches 30, 31 and 32 respectively. The clutches and 31 aremounted u on and in threaded engagement with wide t readed portions 33and 34 on the shaft 10, the threads of which are arran ed or pitched inopposite directions in suc manner that the rotation of the clutch gear24 when moved into engagement with the clutch 30 will cause said clutchto turn on the threads 33, and thus move in the direction of the member24 to securely couple the arts 24 and 30 together, and cause the sha 10.to be driven. In alike manner, the movement of the r clutch 25 intoengagement with the "ch: 31 will cause the clutch 31 to move to theright into firm engagement with the clutch face 25. This constructionprevents any possible slip a e between the parts 2 4--30, 25-31, an a so2632. In the latter case the clutch 32 is mounted upon a collar35threaded in like manner to the threads the collar being fixed to theshaft by threaded engagement therewith as clearly seen, and retained inposition by a-s'et screw 36.

Interposed between the clutch members 25 and26 is a double thrustbearing 37 the central collar 38 of which is in threade enga ent withthe shaft 10 and fixed in position 'by a set screw 39. Another thrustbearing 40 is arranged on the shaft 10 outwardly of and to the left ofthe member 24 and in threaded en gement with the shaft and held inposition y the set screw 41.

A clutch gear 26 does not mesh directly with the gear 23 but is inoperative connection with said gear through an intermediate gear 42having a bearing in the casing 5, the latter gear construction beingemployed for the reverse driving or rotation o the shaft 9 forpropelling the apparatus or vehicle in a backward direction as is commonin motor vehicle transmission apparatus.

" From the foregoing, it will be understood that when the shaft 8 isrotated by the operation of the engine or other source of power, thegears 20, 21, 22 and 23 are also rotated, and thus the clutch gears 24,25 and 26 are correspondingly rotated, all of said are 're'maini in meshin all operations 0 the transmission apparatus. In Fig. 1 of thedrawing, the apparatus is shown in a neutral position; t at is to say,the clutch elemeat 13" is out of engagement with the clutch element 8",and the clutches 24, 25 and 26 areiout of e gement with the clutches 30,Brand 32. lso, the clutch 14 is shown in adisen position. In startingthe vehicle or ot er apparatus at low or first speed, the clutchl4 ismoved into engagement with thegear 9" and the clutch gear 25 is movedinto engagement with the clutch 31. Thus,

.Jarsu 1.

the shaft 9 will be driven from the shaft 8 through the gears 8, 20, 22,25 and the clutch 31 This result may also be effected by a slow shiftingof clutch gears to provide a slight slippgge in the manner of slipping aclutch. In t high or direct operation of the vehicle or shaft rom thesecond speed to the third speed,'the clutch gear 24 is moved out ofengagement with the clutch 30, and the clutch 13 is moved intoengagement with the clutch element 8".

In the above described operations, itwill be understood that anysuitable means may be employed for actuating the several clutch orclutch gears employed. In the use of my im roved apparatus on motorvehicles, it is pre erred that a standard type of shifting be employed.In the several shifts for change speed driving, it will be understoodthat the differential speed of the shaft 10 as compared-with therotation ofthe'respecand movement of the clutch gears 24-25.

This is also true in shifting from forward to reverse or vice versa. Inthe latter case, the

combined clutch gears and clutches will act as brakes to retard theaction or rotation of the shaft 10, it being apparent that the clutchmembers 30, 31 and 32 unthread themselves from their firm engagementposition to a release and from position with reference to the ar clutchmembers 24, 25 and 26.

It W1 1 also be understood that in shifting from'second speed to lowspeed in order to disengage the clutch 30 from the r clutch 24, thedriving of the power 5 aft should be suddenly and momentarily stopped tocause the momentum of the driven shaft 10 to move the clutch 30 to theright out of engagement with the gear 24, at thesame time moving saidgear to the left by the gear shifting means and in the operation ofmoving the gear 25 into engagement with the clutch 31. In making someshifts, it is necessary to increaseor accelerate the power shaftoperationand in other cases to suddenly stop such acceleration to allowthe m0- mentum of the driven shaft to bring about "the disengagement.

re gae a mounted on the shaft 43 and the other two collars on the shaft44. These collars are provided with upwardly directed fingers 45 46 4?and 48 adapted to be engaged by the lower end 49 of a clutch operatinglever 50 pivotally supported in a block 51 carried by a plate or cover52 mounted on the top of the casing 5. The clutch operating lever 50 isof the standard operation type, and in neutral position, the end 49 ispositioned intermediate all of the fingers 45 -48 in moving the lever 50forwardly and to the left for reverse drive, he end 49 of the leverengages the finger 48 and moves the collar 48 backwardly as seen in 1and 2, thus moving the clutch gear 26 into engagement with the clutch32. In the backward movement of the lever 50 and to the left, or inother words, in pulling said lever toward the operator, the finger 47 isengaged andthe sleeve 47 is moved forwardly as seen in the drawing, thusmoving the clutch gear 25 into engagement with the clutch 31. in movingfrom first to second and past the neutral position, wherein the lever 50is moved forwarc ly and backwardly, the sleeve 46 is moved backwardly,as seen in the drawing, and the clutch gear 24 is moved into engagementwith the clutch 30. In like manner, the reverse of the last operationwill move the sleeve 45 forwardly as seen in the drawing to move theclutch 13 into engagement with the clutch element 8 Any suitable means,such for example as spring pressed balls 53 engaging recesses 54 in thesleeves 45-48 may be employed for retaining said sleeves in theirseveral positions. Spring fingers or other means 55 on the respectivesleeves 45-48 may be employed for returning the sleeves 4548 to neutralposition. V

It will be understood that my invention is not necessarily limited toany specific means for actuating the several clutches employed, nor ismy invention limited to the use of ti e transmission on motor vehiclesor similar types of apparatus, as the same may be employed fortransmitting power from a power source to a member or apparatus to bedriven of any kind or class. Further, it will be understood that myinvention is not limited to any particular arrangement of speeds, or tothe number of speeds employed, and various other changes in andmodifications of the construction herein shown and described may be madewithin the scope of the appended claims, without departing from thespirit of my invention or sacrificing its advantages.

Having fully described my invention, what Patent, is

1 In a transmission of the class described,

"afioa'ting main shaft, a supplemental shaft having plurality-of gearsarranged and 'fined'thereto inf spaced'relation, said supplemental shaftbeing in direct operative coniiection with the power shaft, a pluralityof members mounted in spaced relationson the main shaft and free torotate thereon and in constant 'meshwith the gears of the supplementalshaft, and means in screw threaded engagement with the mainshaft andtoward and from which the gear members on the main shaft are movable in.couplingand uncoupling said gear members with respect -to the mainshaft. p 2. In a transmission of the class described, a floating mainshaft, a supplemental shaft having a plurality of gears arranged and '1fixed thereto in spaced relation, said supplemental shaft being indirect operative connection with the power shaft, a plurality of gearmembers mounted in spaced relation on the main shaft and free to rotatethereon and in constant mesh with the gears of the supplemental shaft,means in screw threaded engagement with the main shaft and toward andfrom which the gear members on the 7 main shaft are movable in couplingand uncoupling said gear members with respect to the main shaft, andsaid last named means involving clutch members movable on said screwthreads in the direction of said gear members by the frictionalengagement of the gear members therewith in firmly coupling the gearmembers with the main shaft.

3. A transmission comprising a casing, main and supplemental shaftsmounted in said casing in spaced and parallel relation, gear membersarranged in bearings at opposite sides of the casing, one of said gearmemhere being adapted to be coupled with a power shaft and the otherwith a shaft to be driven, said main shaft being freely rotata ble insaid gear members, said supplemental shaft being geared directly inconnection with said power driven gear member to provide for a constantdriving of the supplemental shaft, transmission gears mounted in spacedrelation on the supplemental shaft, combination gear and clutch unitsdisposed on the main shaft and involving gear and clutch elements havingcooperating beveled faces, the ear element of each unit being slidablyand rotatably mounted on said shaft, and the clutch element thereofbeing in screw threaded engagement with said shaft, and means involvinga gear shifting lever for moving the gear element of each unit in thedirection of the clutch element of said units for coupling therespective units with the main shaft.

4. in a transmission of the class described involving main andsupplemental shafts, a

4 measso power shaft in constant operative engage ment with the suplemental shaft, an a driven shaft adapted to be coupled with the inainshaft and gear unit comprising a (gear n element elidably and rotatablymounte v on the main shaft and in constant mesh with a gear onthesupplemental shaft, and a clutch element arranged adjacent said gearelement and in screw threaded engagement with soidtmain shaft, said gearand clutch elements having cooperating beveled clutch jaw and means formoving the gear element in the direction of the clutch element to firmlyengage said clutch element, moving the 1&5 same on said screw threads inthe direction of the gear element in firmly coupling said 1, gearelement with the main shaft in the operation of rotating the same.

In testimony that I claim the foregoing as my invention I have signed myname this 16th day of June, 1927.

YUKIO KIKUCHI.

